Senator Harry Reid has introduced S. 1348, "the" comprehensive immigration reform bill, but it's really just a placeholder and will either be something very much like last year's S.2611, the CIR bill that passed the Senate, or a bipartisan new bill based on negotiations taking place between Senate Dems, Republicans and the White House. Reid's strategy will largely be shaped by whether a deal with the Republicans has been reached or is very close. Expect an early cloture vote to be taken to see whether the support is there to pass a bill.

The House may also begin marking up its own CIR bill in the next few days, though they'll be closely watching the Senate. I would doubt the House will take up floor debate on a CIR bill if the Senate is not moving its own bill.